In another sign that global warming is likely upon us, a study of ice cores from deep inside a glacier suggests that the last century has been the warmest in 1,000 years in the high Himalayan mountains, with the last decade found to be the hottest period of all. The study, published today in the journal Science, supports other research that has found rapid melting of mountain ice fields in Asia, South America, and Africa. “This is the highest climate record ever retrieved, and it clearly shows a serious warming during the late 20th century,” said lead study author Lonnie Thompson of Ohio State University. “There is no question in my mind that the warming was, in part, if not totally, driven by human activity.”

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